Conventionally, minimally invasive operations including insertion of a diagnostic or therapeutic instrument such as a catheter into a living organism tissue such as a blood vessel have been practiced widely. For example, in the treatment of constriction of the coronary artery of the heart, it is necessary for performing the therapeutic treatment to insert an implement such as a catheter into a blood vessel.
Such insertion of a catheter into a blood vessel is usually performed through a puncture formed in a femoral region. After completion of the therapeutic treatment, therefore, it is necessary to staunch the bleeding through the puncture. In this case, since the blood pressure at the time of bleeding from the femoral artery (bleeding blood pressure) is high, severe work such as applying pressure for a relatively long time with a finger of a hand must be performed by a person involved in the medical treatment.
In recent years, in order to perform such a staunching work easily and assuredly, various devices designed to be inserted through the wound hole to close the hole formed in a blood vessel have been developed. An example of such a device is disclosed in U.S. Pat. No. 5,411,520.
The tissue closing device disclosed in the aforementioned patent includes a filament (suture or the like) gripped by a spring-biased ball at the proximal end of the device. When the device is pulled off, the filament slips while tension on the filament is kept constant, and the device is pulled off. Finally, while pulling the filament in the condition where an anchor (anchor member in the blood vessel) is located at the position of the hole formed in the blood vessel, a nonwoven-fabric plug (seal member) is pushed with a pushing-in pipe or tamping member (is compressed with the filament) to compact the plug. In this manner, the hole formed in the blood vessel is sandwiched (clamped) between the anchor and the compacted plug, and is thereby closed.
In this tissue closing device, notwithstanding the advantage that the device can be immediately put to use when required because the plug is compacted in a tube in an assembled condition, there is a concern that since the plug is kept compacted in the tube very tightly during storage, a load is exerted on the plug and so the plug may show a semi-permanently set shape.
Besides, particularly in the case where a portion corresponding to the plug is composed of a deformable frame-like member, the frame-like member stored for a long time in the state of being put under a load will tend to acquire a semi-permanently set shape (i.e., will undergo plastic deformation). Consequently, it would be difficult to deform the frame-like member for the purpose of embedding it in a living organism, or an excessive force would be needed to effect the deformation.